Appliance devices such as dishwashers, clothes washing machines, dryers, ovens, refrigerators and the like often comprised of electromechanical components. Some of these components have knobs or selector switches so a user may control operational parameters of the appliance. In many cases, the overall operation of the appliance is predefined as a general matter and the settings or selections input by a user merely modify the predefined operation in some way.
For example, the operation of a dishwasher typically involves the processes of filling, washing, draining and rinsing. Such operations involve, among other things, the control of water valves, drain valves and motor relays. The general sequence of such operations is generally predefined. However, user input may be used to alter the sequence of operations within a cycle or to define certain parameters for the entire sequence or parameters within an operation of the sequence. For example, the user input may define whether the wash cycle is normal, light, or heavy. Parameters within an operation of sequence include the temperature of the wash or rinse cycle. Although the general sequence of the overall cycle does not necessarily change dependent upon wash cycle selection, the length or parameters of certain operations within the cycle sequence may change.
A typical user input interface for an electromechanical appliance may include a rotary knob and a plurality of pushbutton switches. The rotary knob may be attached to a mechanical timer having a cam that controls the sequence of operations within the appliance. The cam has a number of followers that trigger the operation of the various appliance components. The cam followers are positioned to cause various operations to be executed in a “programmed” sequence. The user selects a particular cycle by rotating the knob to a particular position associated with the selected cycle. Upon actuation, the cam begins to rotate automatically started from the user selected position to trigger each operation as defined on the cam “program” from the user-selected point forward. The pushbutton switches are used to activate/deactivate various options that are not available through the cam activated program. For example, pushbutton switches may be used to selectively activate such features as a heated dry cycle, a delayed start, or a high temperature wash in a dishwasher, for example.
More recently, electronic controllers, for example, microprocessors and microcontrollers, have replaced the rotary cam control device. The use of electronic controllers provides flexibility and features not typically available in cam control devices. Moreover, as a general matter, replacement of moving parts, such as electromechanical rotating cams, typically increases reliability in products. One aspect of electromechanical appliances not available in appliances with electronic controllers is an indication of the operation in a cycle sequence being performed. In electromechanical appliances, the knob by which the cam was set typically included an arrow or other pointer that pointed towards indicia on the control panel adjacent the knob. By looking at the position of the knob and the indicia to which it pointed, the user could ascertain the operation being performed by the appliance.
To provide an indication of the operation being performed, many appliances having electronic controllers also include indicators such as small electrical lights or light emitting diodes (LEDs). These indicators are typically located adjacent indicia on an appliance control panel. As the electronic controller deactivates one operation and activates another, the controller also operates one or more switches to turn off the indicator beside indicia identifying the operation being deactivated and turning on the indicator beside indicia identifying the operation being activated. In this manner, the user is provided visual feedback regarding the current operational state of the appliance.
The use of electronic controllers has added to the complexity of servicing appliances. Small electronic integrated circuits do not lend themselves to the methods of troubleshooting and repair that have historically been used with mechanical and electromechanical devices. Accordingly, malfunctions in an electronically controlled appliance are more difficult to diagnose and resolve than those of the old, mechanical cam controlled devices.
Some have proposed the incorporation of infrared and radio communication devices in appliances having microprocessors for the purpose of communicating troubleshooting data. However, infrared and radio communication modules add appreciable expense to the manufacture of appliances. Because appliance manufacturers operate with relatively low profit margins, an increase of even one dollar in cost is multiplied by the production output, which may be in the millions of units. Thus, the additional expense of long range communication modules, such as infrared and radio communication devices, may significantly impact the bottom line of an appliance manufacturer.
In an effort to provide a low cost communication interface for an appliance having an electronic controller, the assignee of the present invention has developed an optical communication interface that effectively uses the indicators of the appliance for communication. This optical communication interface is the subject of pending U.S. patent applications bearing Ser. Nos., 10/264,888 filed Oct. 4, 2002, and 10/348,305 filed Jan. 21, 2003, that are entitled “Appliance Control Communication Methods and Apparatus,” and “System and Method for Communicating with an Appliance Through a Light Emitting Diode,” respectively. These applications are hereby expressly incorporated by reference. As set forth in these applications, an electronic controller may control the on/off status of an indicator to provide a digital optical signal that may be received by an externally located phototransistor or other LED. The digital signal from the appliance may be used to provide data from the appliance to external data storage for analysis or transmission. Additionally, an external device may transmit a signal to the appliance in a reverse manner because a LED used as an indicator on an appliance may respond as a phototransistor to light and generate a corresponding electrical signal. This signal may be received by the electronic controller and used to modify data or program control within the appliance.
While the optical interface may support communication with an electronic controller so data may be exchanged with an appliance, data communication problems also arise in the management of the interface and the communication received through it. One problem that arises regards the amount of resources to allocate to the management of the communication interface. In most electronic controllers used in appliances, program and data memory space are typically at a premium. Consequently, communication management of the interface needs to be efficient. Another problem with management of the interface in an appliance is the validity of the data. That is, the controller and the external device need to determine whether data received is the data that was transmitted. Furthermore, the electronic controller needs to be able to determine whether all data elements of a data message have been received.
While network protocols are available that provide data message verification and that assess whether complete messages have been received, such protocols and programs that implement them are not good candidates for optical interface control in an appliance. For one, they require a lot of memory resources. For another, they assume the coupling of a device to a network with each device having an unique identifier. The processing of the identifier and forwarding of messages not addressed to the recipient requires overhead processing and resources that may not be available in an appliance.
Consequently, there is a need for communication management in an appliance without significantly increasing the costs of manufacturing an appliance.
There is a need for communication management that does not require a fully orbed network communication controller and program.